Goggle type display system

ABSTRACT

To provide a goggle type display device system that can prevent harm to user&#39;s health. If anomaly is recognized in mind and body of a user, first video signals provided from an external device stop being displayed on LCD panels and, instead, outside scenery taken by CCD image capture elements is displayed. The user may be alarmed by this about anomaly of his or her body and, further, relaxed by looking at the outside scenery presented.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a goggle type display devicesystem worn by a user on the head.

[0003] 2. Description of the Related Art

[0004] In recent years, goggle type display devices worn by a user onthe head are gaining popularity. Those goggle type display devices, alsocalled as HMDs (head mount displays), have lenses for magnifying animage to form its virtual image and a display devices, such as liquidcrystal panels, arranged in a shorter distance than the focal distanceof the lenses. A user observes a display on the liquid crystal panelsthrough the lenses to have the magnified image. Thus, in spite ofsmallness of the devices, the user can enjoy a large screen display.

[0005] However, the user, observing the virtual image through thelenses, will have very sore eyes. If this eyestrain lasts whileuntreated, in the worst cases, user's eyesight may be damaged even by ashort time use, which is a problem with those display devices.

SUMMARY OF THE INVENTION

[0006] The present invention has been made in view of the above problemand, therefore, an object of the present invention is to provide agoggle type display device system the use of which causes no harm touser's health.

[0007] According to the present invention, there is provided a goggletype display device system comprising:

[0008] two liquid crystal display devices;

[0009] first video signals inputted from an external video signalsupplying device;

[0010] two image capture elements for converting outside images intosecond video signals;

[0011] a sensor for converting vital information of a user into a vitalinformation signal; and

[0012] a video signal control circuit for providing the two liquidcrystal display devices with video signals, characterized in that

[0013] the video signal control circuit provides the two liquid crystaldisplay devices with the first video signals or the second video signalson the basis of an index obtained by numerically processing the vitalinformation signal.

[0014] According to the present invention, there is provided a goggletype display device system comprising:

[0015] two liquid crystal display devices;

[0016] first video signals inputted from an external video signalsupplying device;

[0017] two first image capture elements for converting outside imagesinto second video signals;

[0018] two second image capture elements for converting images of user'seyes into third video signals;

[0019] a sensor for converting vital information of a user into a vitalinformation signal; and

[0020] a video signal control circuit for providing the two liquidcrystal display devices with video signals, characterized in that

[0021] the video signal control circuit provides the two liquid crystaldisplay devices with the first video signals or the second video signalson the basis of an index obtained by numerically processing the thirdvideo signals and the vital information signal.

[0022] According to the present invention, there is provided a goggletype display device system comprising:

[0023] two liquid crystal display devices;

[0024] first video signals inputted from an external video signalsupplying device;

[0025] two image capture elements for converting outside images intosecond video signals;

[0026] a sensor for converting vital information of a user into a vitalinformation signal; and

[0027] a video signal control circuit for providing the two liquidcrystal display devices with video signals, characterized in that:

[0028] the video signal control circuit calculates the degree of fatigueof the user on the basis of a chaos attractor index obtained bynumerically processing the vital information signal;

[0029] the video signal control circuit provides the two liquid crystaldisplay devices with the first video signals when the degree of fatigueis equal to or less than a predetermined level; and

[0030] the video signal control circuit provides the two liquid crystaldisplay devices with the second video signals when the degree of fatigueexceeds the predetermined level.

[0031] According to the present invention, there is provided a goggletype display device system comprising:

[0032] two liquid crystal display devices;

[0033] first video signals inputted from an external video signalsupplying device;

[0034] two image capture elements for converting outside images intosecond video signals;

[0035] another pair of image capture elements for converting images ofuser's eyes into third video signals;

[0036] a sensor for converting vital information of a user into a vitalinformation signal; and

[0037] a video signal control circuit for providing the two liquidcrystal display devices with video signals, characterized in that:

[0038] the video signal control circuit calculates the degree of fatigueof the user on the basis of a chaos attractor index obtained bynumerically processing the third video signals and the vital informationsignal;

[0039] the video signal control circuit provides the two liquid crystaldisplay devices with the first video signals when the degree of fatigueis equal to or less than a predetermined level; and

[0040] the video signal control circuit provides the two liquid crystaldisplay devices with the second video signals when the degree of fatigueexceeds the predetermined level.

[0041] The first image capture elements may be CCD image captureelements or image sensors.

[0042] The second image capture elements may be CCD image captureelements or image sensors.

[0043] The vital information of a user may be pulse wave, bloodpressure, body temperature or dilated degree of the pupils of the eyes.

[0044] The sensor may be a pulse wave sensor, a blood pressure sensor ora body temperature sensor.

[0045] The pulse wave sensor, the blood pressure sensor or the bodytemperature sensor may be arranged in headphones.

[0046] The image sensors may be formed integrally with the liquidcrystal display devices.

[0047] The liquid crystal display devices may be reflection type liquidcrystal display devices.

[0048] The liquid crystal display devices each have a back light thatmay use red LEDs, green LEDs and blue LEDs.

[0049] The liquid crystal display devices may be driven by a fieldsequential system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0050]FIG. 1 is a constructional diagram schematically showing a goggletype display device system according to Embodiment 1 of the presentinvention;

[0051]FIG. 2 is a perspective view showing the schematic construction ofthe goggle type display device system according to Embodiment 1 of thepresent invention;

[0052]FIG. 3 is a perspective view showing the appearance of the goggletype display device system according to Embodiment 1 of the presentinvention;

[0053]FIG. 4 is a view showing headphones for use in a goggle typedisplay device system of Embodiment 1 of the present invention;

[0054]FIG. 5 is a flow chart showing the operation of the goggle typedisplay device system according to Embodiment 1 of the presentinvention;

[0055]FIG. 6 is a flow chart showing the operation of the goggle typedisplay device system according to Embodiment 2 of the presentinvention;

[0056]FIG. 7 is still a flow chart showing the operation of the goggletype display device system according to Embodiment 3 of the presentinvention;

[0057]FIG. 8 is a perspective view showing the schematic construction ofa goggle type display device system according to Embodiment 4 of thepresent invention;

[0058]FIG. 9 is a perspective view showing the appearance of the goggletype display device system according to Embodiment 4 of the presentinvention;

[0059]FIG. 10 is a view showing the schematic construction of a goggletype display device system according to Embodiment 5 of the presentinvention;

[0060]FIG. 11 is a perspective view showing the appearance of the goggletype display device system according to Embodiment 5 of the presentinvention;

[0061]FIG. 12 is a view showing the schematic construction of a goggletype display device system according to Embodiment 6 of the presentinvention;

[0062]FIG. 13 is a perspective view showing the appearance of the goggletype display device system according to Embodiment 6 of the presentinvention;

[0063]FIG. 14 is a view showing exemplary points of measurement forobtaining vital information of a user, which is utilized in a goggletype display device system of Embodiment 1 of the present invention;

[0064]FIG. 15 shows an example of an LCD panel with built-in imagesensors for use in the goggle type display device system according toEmbodiment 5 of the present invention;

[0065]FIGS. 16A to 16E are views showing an example of a manufacturingprocess of an LCD panel for use in a goggle type display device systemof Embodiment 7 of the present invention;

[0066]FIGS. 17A and 17 B are views showing the example of themanufacturing process of the LCD panel for use in a goggle type displaydevice system of Embodiment 7 of the present invention;

[0067]FIG. 18 is a timing chart of a field sequential driving method ofEmbodiment 1 of the present invention;

[0068]FIGS. 19A and 19B are views showing a structure of an EL displaydevice of Embodiment 9 of the present invention;

[0069]FIGS. 20A and 20B are views showing a structure of an EL displaydevice of Embodiment 10 of the present invention;

[0070]FIG. 21 is a view showing a cross section of a pixel portion inthe an EL display device of Embodiment 11 of the present invention;

[0071]FIGS. 22A and 22B are views showing a structure of the pixelportion in an EL display panel and a circuit structure for the pixelportion, respectively, of Embodiment 11 of the present invention;

[0072]FIG. 23 is a view showing a structure of a pixel portion in an ELdisplay device of Embodiment 12 of the present invention;

[0073]FIGS. 24A to 24C are views showing circuit structures for pixelportions in EL display devices of Embodiment 13 of the presentinvention;

[0074]FIG. 25 is a diagram showing the electro-optical characteristic ofmonostable FLC according to Embodiment 8 of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0075] Hereinafter, embodiments of the present invention will bedescribed. Incidentally, following embodiments are examples preferredand are not intended to restrict thereto a goggle type display devicesystem of the present invention.

EMBODIMENT 1

[0076]FIG. 1 schematically shows a constructional diagram of a goggletype display device system according to this embodiment. Referencesymbol 101 denotes a goggle type display device, and denoted by 102-Land 102-R are LCD panels (liquid crystal panels). Throughout thespecification, there can be found reference symbols with appendantcharacters of “-R” or “-L”, which indicates that members denoted bythose reference symbols are components either for the right eye or forthe left eye. Reference symbols 105-L and 105-R denote LED back lightseach having a photoconductive plate 103 (not shown) and an LED 104 (notshown). The LED 104 includes a plurality of LEDs which emit red light,green light and blue light, respectively, and serves as a white lightsource as a whole. The photoconductive plate 103 is to uniformlyirradiate all over the display surfaces of the LCD panels 102 with lightemitted from those plural LEDs. Reference symbols 106-L and 106-R denotelenses. Denoted by 107-L and 107-R are CCD image capture elements thatcapture images of user's left eye and right eye and convert the imagesinto a third video signal L and a third video signal R, respectively.Another pair of CCD image capture elements 108-L and 108-R captureoutside scenery (images) and convert it into a second video signal L anda second video signal R, respectively. Inputted to a video signalcontrol circuit 109 are: a first video signal L and a first video signalR which are sent from an external device; a vital information signal ofa user; the third video signal L and the third video signal R which aresent from the CCD image capture elements 107-L and 107-R; and the secondvideo signal L and the second video signal R which are sent from the CCDimage capture elements 108-L and 108-R. The video signal control circuit109 provides the LCD panels 102-L and 102-R with a video signal L and avideo signal R, respectively. Reference symbols 110-L and 110-R denoteuser's left eye and right eye, respectively.

[0077] The goggle type display system of this embodiment includes, otherthan those components, a sensor for obtaining vital information of auser and converting it into the vital information signal, speakers orheadphones for outputting voice, music and the like, a VCR or a computerfor supplying video signals, etc.

[0078]FIG. 2 shows in a perspective view the construction of the goggletype display device system of this embodiment shown in FIG. 1.

[0079]FIG. 3 is a view showing the appearance of the goggle type displaydevice in this embodiment. Drawn as a perspective view, FIG. 3 showsevery component of the device.

[0080] The arrangement in FIG. 3 does not limit the arrangement of theCCD image capture elements 107-L, 107-R for monitoring user's eyes andof the CCD image capture elements 108-L, 108-R for capturing outsideimages. Depending on design, the arrangement of these CCD image captureelements may be changed.

[0081] In this embodiment, display is accomplished by driving the LCDpanels with the field sequential method, using the LED back lights.

[0082]FIG. 18 shows a timing chart of the field sequential drivingmethod. In the timing chart of the field sequential driving method,there are shown a starting signal for video signal writing (V syncsignal), lighting timing signals for red (R), green (G) and blue (B)LEDs, and a video signal (VIDEO). Tfs indicate frame periods. TR, TG andTB indicate LED lit-up periods of red (R), green (G) and blue (B),respectively.

[0083] Of the video signals supplied to the LCD panels, for example, R1is a signal that is compressed in time-base to have a ⅓ size of anoriginal video signal inputted from the external and corresponding tored; G1 is a signal that is compressed in time-base to have a ⅓ size ofan original video signal inputted from the external and corresponding togreen; and B1 is a signal that is compressed in time-base to have a ⅓size of an original video signal inputted from the external andcorresponding to blue.

[0084] In the field sequential driving method, the LEDs of R, G and Bare lit up in order during the LED lit-up periods, i.e., TR period, TGperiod and TB period, respectively. During the lit-up period of the redLED (TR), a video signal corresponding to red (R1) is supplied to theLCD panels to write therein a red image for one screen. During the litupperiod of the green LED (TG), a video signal corresponding to green (G1)is supplied to the LCD panels to write therein a green image for onescreen. During the lit-up period of the blue LED (TB), a video signalcorresponding to blue (B1) is supplied to the LCD panels to writetherein a blue image for one screen. Formation of one frame takes thesethree times operations of image writing.

[0085] Therefore, a color LCD panel driven by the field sequentialdriving method can acquire a resolution three times as high as that of aconventional color display device.

[0086] Incidentally, a back light of a cathode-ray tube may be used todisplay in the goggle type display device of the present invention.

[0087] Here, operation and function of the goggle type display system ofthis embodiment will be described. See once more FIG. 1. According tothe goggle type display system of this embodiment, in a normal use, thevideo signal control circuit provides the LCD panels 102-L and 102-Rwith, respectively, the first video signal L and the first video signalR which are supplied from an external device. As an example of theexternal device, a personal computer, a portable information terminaland a VCR are enumerated. A user observes an image displayed on the LCDpanels 102-L and 102-R through the lenses 106-L and 106-R. The user seesthe image displayed on the LCD panels as a magnified image (virtualimage) in a location far away from the actual position of the LCDpanels.

[0088] The goggle type display device 101 of this embodiment is equippedwith the CCD image capture elements 107-L and 107-R for monitoring eyeballs of a user and for converting the images of the eyes into electricsignals. These CCD image capture elements 107-L and 107-R monitor theimages of user's eyes during the device is in use, and input videosignals of the eyes (third video signals) to the video signal controlcircuit 109. The video signal control circuit 109 numerically processesthe input video signals of the eyes (third video signals) to calculatethe degree of congestion in the user's eyes.

[0089] The goggle type display device system of this embodimentcomprises headphones 401 as shown in FIG. 4. In FIG. 4, referencesymbols 402-R and 402-L denote speaker units. A band is designated by403. Denoted by 404 is a pulse wave sensor made to fit to a part ofuser's ear for detecting the pulse wave of the user. Antenna 405receives voices and music on electric waves from the external device andtransmits information on the user's pulse waves detected by the pulsewave sensor to the video signal control circuit 109 of the goggle typedisplay device 101.

[0090] Referring to FIG. 5, there is shown a operational flow chart ofthe goggle type display device system according to this embodiment. Inthe goggle type display device system according to this embodiment,normally, the video signal control circuit provides the LCD panels withthe first image signals sent from the external device (such as apersonal computer or a VCR). The pulse wave information measured by thepulse wave sensor that is attached to the headphones is inputted to thevideo signal control circuit 109. Though vital information signals fromthe sensor is inputted to the video signal control circuit 109 in thisembodiment, the vital information signals from the sensor may be sentonce to the external device to be then inputted from the external deviceto the video signal control circuit 109.

[0091] When the pulse wave of the user is smaller than a predeterminedvalue, the system judges that “the pulse wave is normal” and proceeds tothe next step. When the pulse wave of the user is larger than thepredetermined value, the system judges that “the pulse wave is abnormal”and outside scenery taken by the CCD image capture elements 108-L and108-R is displayed on the LCD panels.

[0092] The images of the user's eyes captured by the CCD image captureelements 107-L and 107-R are, after converted into video signals,inputted to the video signal control circuit 109. The video signalcontrol circuit 109 performs image processing on the video signals ofthe user's eyes to calculate the degree of congestion in the user'seyes.

[0093] When the degree of congestion in the user's eyes which iscalculated on the basis of the video signals of the user's eyes issmaller than a predetermined value, the system judges that “the degreeof congestion is normal” and proceeds to the next normal step. When thedegree of congestion in the user's eyes is larger than the predeterminedvalue, the system judges that “the degree of congestion is abnormal” andoutside scenery taken by the CCD image capture elements 108-L and 108-Ris displayed on the LCD panels.

[0094] The above operations are repeated.

[0095] As shown in FIG. 14, vital information of a user can be obtainedfrom various regions of user's body (regions a to e, and others).

[0096] If pulse wave anomaly or eye congestion anomaly of the user isrecognized, as described above, the first video signals provided fromthe external device stop being displayed on the LCD panels and outsidescenery taken by the CCD image capture elements 108-L and 108-R isdisplayed instead. The user may be alarmed by this about anomaly of hisor her body and, further, relaxed by looking at the outside scenerypresented.

EMBODIMENT 2

[0097] In this embodiment, a description will be given on a case where ablood pressure sensor is installed in addition to the structure of thegoggle type display device of the above Embodiment 1. Incidentally,Embodiment 2 is the same as Embodiment 1 except for the installment ofthe blood pressure sensor, and hence Embodiment 1 can be referred withregard to the detailed structure of this embodiment.

[0098] Referring to FIG. 6, the drawing shows an operational flow chartof a goggle type display device system of this embodiment. According tothe goggle type display system of this embodiment, in a normal use, avideo signal control circuit provides LCD panels 102-L and 102-R withfirst video signals L and R that are supplied from an external device.

[0099] As described in Embodiment 1, when the pulse wave of a user issmaller than a predetermined value, the system judges that “the pulsewave is normal” and proceeds to the next normal step. When the pulsewave of a user is larger than the predetermined value, the system judgesthat “the pulse wave is abnormal” and outside scenery taken by CCD imagecapture elements 108-L and 108-R is displayed on the LCD panels.

[0100] Then, information about user's blood pressure is obtained from asensor. This blood pressure information is inputted to the video signalcontrol circuit. When the user's blood pressure is smaller than apredetermined value, the system judges that “the blood pressure isnormal” and proceeds to the next step. When the user's blood pressure islarger than the predetermined value, the system judges that “the bloodpressure is abnormal” and outside scenery taken by the CCD image captureelements 108-L and 108-R is displayed on the LCD panels.

[0101] When the degree of congestion in user's eyes which is calculatedon the basis of the video signals of the user's eyes is smaller than apredetermined value, the system judges that “the degree of congestion isnormal” and proceeds to the next normal step. When the degree ofcongestion in the user's eyes is larger than the predetermined value,the system judges that “the degree of congestion is abnormal” andoutside scenery taken by the CCD image capture elements 108-L and 108-Ris displayed on the LCD panels.

[0102] Thus, in this embodiment also, upon recognition of pulse waveanomaly, blood pressure anomaly or eye congestion anomaly of the user,displaying on the LCD panels the first video signals supplied from theexternal device is stopped and outside scenery taken by the CCD imagecapture elements 108-L and 108-R is displayed instead. The user may bealarmed by this about anomaly of his or her body and, further, relaxedby looking at the outside scenery presented.

EMBODIMENT 3

[0103] A goggle type display device system of this embodiment is thesame in structure as the goggle type display device system of the aboveEmbodiment 1. However, the system of this embodiment uses chaos theoryto decide, on the basis of user's vital information, whether or notswitching from an image sent from an external device to outside imagesent from CCD image capture elements is needed.

[0104] Reference is made to FIG. 7. The goggle type display devicesystem of this embodiment obtains chaos attractor information on thebasis of the vital information presented by a pulse wave sensor, a bloodpressure sensor, a body temperature sensor or CCD image capture elementsthat capture images of user's eyes.

[0105] First of all, what “chaos” designates is explained. In nature orin an artificial world, there are a lot of predictable phenomena. Forinstance, Halley's comet or an operating artificial satellite is one ofsuch phenomena, and to predict the comet's or satellite's location andact correspondingly is within the realm of possibility. We might see itis the deterministic predictability, where there is no indefinitionbetween cause and effect, that forms an aspect of the great power ofscience.

[0106] However, weather is often forecasted wrong despite the assumptionthat it is the motion of the atmosphere which obeys the physical law. Ithas been said that such a phenomenon as weather in which causal relationseems unclear includes disorderly factors, and the phenomenon has beenbelieved to be correctly predicted if, basically, a perfect parameterfor describing the system is known. In other words, if it is possible tocollect sufficient information about the system.

[0107] Namely, the disorderliness has been considered as a result oflack of information about the multi-degree-of-freedom system. Againstthat notion, the discovery of the fact that even a simple system havingmerely small degree of freedom (third dimension or higher) sometimesacts disorderedly leads to finding of the existence of what seems tofollow determinism but is disorderly in essence. The disorderliness assuch has become called chaos.

[0108] The concept of chaos, however, has not been standardized yet. Itcovers vast definition range as does the theory of evolution and,depending on objects, it even gives us the impression that the conceptgets ahead of us. Therefore, this specification dares to settle on theconcept of chaos as follows.

[0109] The chaos means a phenomenon that is random in essence for itsvery intricate behavior occurring non-linearly despite being a systemwith a deterministic law. The chaos further implies that a complex orderand law may exist behind a seemingly disorderly or orderless phenomenonthat lacks any law and predictability.

[0110] The topology that characterizes the behavior of chaos is calledchaos attractor, which is a mathematical structure where the systembehavior generating chaos converges.

[0111] From those points of view, the pulse wave detected in a body isknown to act chaotically. A recognized authority in this field reportedat an academic meeting that finger tip pulse wave showed chaos mentaland physical information. At the same time, a medical diagnostic methodutilizing that chaos was filed for patent by this person (JapanesePatent Application Laid-open No. Hei 4-208136).

[0112] Then, the goggle type display device system of this embodimentactively utilizes the fact that the chaos attractor obtained bynumerically processing user's vital information such as pulse wave orblood pressure and Lyapunov index indicating to what degree this datafits the definition condition of the chaos are correlated to mental andphysical information of a user.

[0113] Based on this, vital information of the user is obtained byforming chaos attractor from numerically processing user's pulse wave,blood pressure, degree of eye congestion, body temperature, etc. Theobtained vital information and Lyapunov index that is a numeric valueshowing to what degree this data fits the definition condition of thechaos are used to know mental and physical conditions of the user.

[0114] An example of means for obtaining the pulse wave includes asensor that has a combination of an infrared light emitting diode and aphoto sensor, and one that utilizes a semiconductor pressure sensor.

[0115] Here, the relationship between the mental and physical conditionsand the chaos attractor of the pulse wave is as follows.

[0116] (1) The chaos attractor of the pulse wave acutely reflects themental state and shows the peculiar topology.

[0117] (2) The chaos attractor obtained from the pulse wave has, inaddition to the basic structure common to human, a personal structure ofhis/her own, and varies depending on the mental state or on illness.

[0118] (3) Generally, when the mental state or physiological state isunstable or during illness, the whole structure of the attractor becomessimple, small and structureless. Further, the rhythm takes mechanicaland monotonous periodic structure. Namely, the attractor becomes lesschaotic.

[0119] (4) In good health, the whole structure is complicated anddynamic, and the local structure is also complicated to exhibit a wound,twisted or screwed structure. And the rhythm becomes aperiodic. Namely,life in good health is fully chaotic.

[0120] (5) When one concentrates his or her mind on something, the chaosattractor becomes complicated and local structure such as wound ortwisted structure appears. On the other hand, when one is put under astress exceeding a certain threshold to feel tired, the structure getssimple and the local structure is lost.

[0121] Based on what is expressed in the above items, current conditionof a user is classified into several types. An image displayed on theLCD panels is switched in accordance with the classification.

[0122] Here, reference is again made to FIG. 7. The goggle type displaydevice of this embodiment normally provides the LCD panels with videosignals from the external device.

[0123] Vital information (pulse wave, blood pressure, body temperature,etc.) obtained from a user is inputted in a video signal controlcircuit. The video signal control circuit numerically processes thevital information, judges to which level that is previously set theresulting value corresponds, and calculates Lyapunov index on the basisof that corresponding level. This numerical arithmetic processing andcalculation of Lyapunov index require computer processing. However, thisprocessing method and the expression for chaos attractor afterprocessing do not involve with any fixed equation, nor processingprocedure, and may be expressed arbitrarily.

[0124] The level previously set to calculate Lyapunov index may have asmany stages as suited, depending on how to classify or sort the chaosattractor. For example, the classifications “stimulated” and “notstimulated” make two stages. To add to the two stages theclassifications “mind concentrated” and “mind distracted” makes thetotal of four stages. The classifications “fatigued” and “not fatigued”may be added thereto to make the total of six stages. At this stage, animage to be supplied to the LCD panels is switched. That is, when a useris in the “fatigued” stage, first video signals supplied from theexternal device stop being displayed on the LCD panels and outsidescenery taken by CCD image capture elements 108-L and 108-R is displayedinstead. The user may be alarmed by this about anomaly of his or herbody and, further, relaxed by looking at the outside scenery presented.

[0125] As to the chaos theory, techniques disclosed in the followingdocuments by the present applicant may be applied: U.S. Pat. Nos.5,395,110 and 5,800,265, Japanese Patent Nos. 2722302, 2673768 and2722303, and Japanese Patent Application Laid-open Nos. Hei 6-134098 andHei 8-229236.

EMBODIMENT 4

[0126] A goggle type display system of this embodiment is slightlydifferent in structure from the goggle type display device systemsdescribed in the above Embodiments 1 to 3. A perspective view in FIG. 8shows a schematic constructional diagram of the goggle type displaydevice system of this embodiment. Reference symbols 802-L, 802-R denoteLCD panels; 803-L, 803-R, photoconductive plates; and 804-L, 804-R,LEDs. The photoconductive plates 803-L, 803-R and the LEDs 804-L, 804-Rconstitute LED back lights 805-L, 805-R. The LEDs 804 include aplurality of red LEDs, green LEDs and blue LEDs and, as a whole, serveas white light sources. The photoconductive plates 803 are to uniformlyirradiates the LCD panels 802 with light emitted from the plural LEDs.Denoted by 806-L, 806-R are lenses; 807-L, 807-R, CCD image captureelements for capturing images of user's left and right eyes to convertthe images into a third video signal L and a third video signal R,respectively; 808-L, 808-R, another pair of CCD image capture elementsfor taking outside scenery (images) to convert it into a second videosignal L and a second video signal R, respectively; and 809-L, 809-R,mirrors for making images on the LCD panels enter into the lenses.

[0127] Though not shown in FIG. 8, the goggle type display device ofthis embodiment has a video signal control circuit 810. The video signalcontrol circuit 810 receives inputs from the external, that is, firstvideo signals from an external device, a vital information signal of auser, the third video signal L and third video signal R from the CCDimage capture elements 807-L, 807-R, and the second video signal L andsecond video signal R from the CCD image capture elements 808-L, 808-R.Also, the video signal control circuit 810 provides the LCD panels802-L, 802-R with a video signal L and a video signal R.

[0128] The goggle type display system of this embodiment comprises,other than these components, a sensor for obtaining user's vitalinformation to convert it into the vital information signal, speakers orheadphones for outputting voice or music, etc.

[0129]FIG. 9 is a view showing the appearance of the goggle type displaydevice of this embodiment. Drawn as a perspective view, FIG. 9 showsevery component of the device.

[0130] Incidentally, arrangement of the CCD image capture elements807-L, 807-R for monitoring user's eyes and CCD image capture elements808-L, 808-R for taking outside images is not limited to the one shownin FIG. 8. Depending on design, the arrangement of these CCD imagecapture elements may be changed.

[0131] Though LED back lights are used for back lights of the LCD panelsin the goggle type display device of this embodiment, cathode-ray tubeback lights may be used instead.

[0132] Any of the above Embodiments 1 to 3 may be referred with regardto the operation of the goggle type display device of this embodiment.

EMBODIMENT 5

[0133] In a goggle type display device of this embodiment, CCD imagecapture elements for monitoring user's eyes are omitted and, instead,image sensors integrally formed on LCD panels are used to monitor user'seyes.

[0134]FIG. 10 is a schematic constructional diagram showing a goggletype display device system of this embodiment. Reference symbol 1001denotes a goggle type display device and 1002-L, 1002-R denote LCDpanels with built-in image sensors. The image sensors incorporated inthe LCD panels 1002-L and 1002-R convert images of user's eyes into athird video signal L and the third video signal R, respectively.Reference symbols 1005-L, 1005-R denote LED back lights each having aphotoconductive plate 1003 (not shown) and an LED 1004 (not shown).Lenses are denoted by 1006-L and 1006-L. CCD image capture elements1007-L, 1007-R take outside scenery (images) to convert it into a secondvideo signal L and a second video signal R. Reference symbol 1009denotes a video signal control circuit that receives inputs from theexternal, namely, first video signals from an external device, a vitalinformation signal of a user, the second video signal L and second videosignal R from the CCD image capture elements 1007-L, 1007R, and thethird video signal L and third video signal R from the image sensorsincorporated in the LCD panels 1002-L, 1002-R. Also, the video signalcontrol circuit 1009 provides the LCD panels 1002-L, 1002-R with a videosignal L and a video signal R.

[0135] The goggle type display system of this embodiment comprises,other than these components, a sensor for obtaining user's vitalinformation to convert it into a vital information signal, speakers orheadphones for outputting voice or music, etc.

[0136]FIG. 11 shows in perspective view the structure of the goggle typedisplay device system of this embodiment shown in FIG. 10.

[0137]FIG. 15 shows an example of the LCD panels with built-in imagesensors used in the goggle type display system of this embodiment.Though the LCD panel shown in FIG. 15 has four relatively small imagesensors incorporated therein, the panels are not limited to thisexample.

[0138] Any of the above Embodiments 1 to 3 may be referred with regardto the operation of the goggle type display device of this embodiment.

EMBODIMENT 6

[0139] In a goggle type display device of this embodiment, CCD imagecapture elements for monitoring user's eyes and CCD image captureelements for monitoring outside scenery are omitted and, instead, imagesensors integrally formed on the LCD panels are used to monitor user'seyes and outside scenery.

[0140]FIG. 12 is a schematic constructional view showing a goggle typedisplay device system of this embodiment. Reference symbol 1201 denotesa goggle type display device and 1202-L, 1202-R denote LCD panels withbuilt-in image sensors. The image sensors incorporated in these LCDpanels 1202-L, 1202-R convert images of user's eyes into third videosignals L, R and take outside scenery (images) to convert it into asecond video signal L and a second video signal R. Reference symbols1205-L, 1205-L denote LED back lights each having a photoconductiveplate 1203 (not shown) and an LED 1204 (not shown). Lenses aredesignated by 1206-L and 1206-R. Reference symbol 1209 denotes a videosignal control circuit that receives inputs from the external, namely,first video signals from an external device, vital information signalsof a user, the second video signal L, second video signal R, third videosignal L and third video signal R from the image sensors incorporated inthe LCD panels 1202-L, 1202-R. Also, the video signal control circuit1209 provides the LCD panels 1202-L, 1202-R with a video signal L and avideo signal R, respectively.

[0141] The goggle type display system of this embodiment comprises,other than these components, a sensor for obtaining user's vitalinformation to convert it into the vital information signal, speakers orheadphones for outputting voice or music, etc.

[0142]FIG. 13 shows in perspective view the structure of the goggle typedisplay device system of this embodiment shown in FIG. 12.

[0143] Any of the above Embodiments 1 to 3 may be referred with regardto the operation of the goggle type display device of this embodiment.

EMBODIMENT 7

[0144] Now, a description will be given below on an example of a methodfor manufacturing the LCD panels used in the above Embodiments 1 to 6.This embodiment shows a case, with reference to FIGS. 16A to 17B; wherea plurality of TFTs (thin film transistors) are formed on a substratehaving an insulating surface, and an active matrix circuit as a displayunit, a source signal line driver circuit, a gate signal line drivercircuit, a digital data dividing circuit and other peripheral circuits,etc., which are all together formed on the same single substrate. Theexample below shows a pixel TFT that is a member constituting the activematrix circuit and a CMOS circuit that is a basic circuit for the othercircuits (the source signal line driver circuit, the gate signal linedriver circuit and the other peripheral circuit), which are formedsimultaneously. The example below gives a description on a manufacturingmethod of the CMOS circuit in which one gate electrode is provided foreach of a p-channel TFT and an n-channel TFT. However, it is alsopossible to similarly fabricate a CMOS circuit with a TFT that has aplurality of gate electrodes, such as a double gate type TFT or a triplegate type TFT. Though the pixel TFT in the example below is a doublegate n-channel TFT, it may be a single gate TFT, a triple gate TFT, etc.

[0145] See FIGS. 16A to 17B. First, a non-alkaline glass substraterepresentative of which is, for example, Corning 1737 glass substrate isused for a substrate 7001. On one surface of the substrate 7001 where aTFT is to be formed, a base film 7002 made from silicon oxide is formedto have a thickness of 200 nm. The base film 7002 may be a laminatedfilm formed by layering the silicon oxide film and a silicon nitridefilm, or may be a single layer of silicon nitride film. Also, the basefilm 7002 may have a layered structure of a silicon nitride oxide filmand a silicon oxide film.

[0146] Next, an amorphous silicon film with a thickness of 50 nm isformed on this base film 7002 by plasma CVD. Though depending onhydrogen content of the amorphous silicon film, the film is preferablyheated up to 400 to 500° C. for dehydrogenation, reducing the hydrogencontent of the amorphous silicon film to 5 atm % or less. Thencrystallization step is performed on the dehydrogenated film to form acrystalline silicon film.

[0147] This crystallization step may employ a known lasercrystallization technique or thermal crystallization technique. In thisembodiment, KrF excimer laser light of pulse oscillation type isconverged into a linear beam to irradiate the amorphous silicon film,forming the crystalline silicon film.

[0148] Used in this embodiment as an initial film is an amorphoussilicon film, but a microcrystal silicon film may be used as the initialfilm. Alternatively, a crystalline silicon film may be directly formed.

[0149] The thus formed crystalline silicon film is patterned to formisland-like semiconductor active layers 7003, 7004, 7005.

[0150] A gate insulating film 7006 containing mainly silicon oxide orsilicon nitride is then formed to cover the semiconductor layers 7003,7004, 7005. A silicon nitride oxide film with a thickness of 100 nm isformed here by plasma CVD. Though not shown in FIGS. 16A to 16E, formedon the surface of the gate insulating film 7006 by sputtering are: atantalum (Ta) film as a first conductive film having a thickness of 10to 200 nm, for example, 50 nm; and an aluminum (Al) film as a secondconductive film having a thickness of 100 to 1000 nm, for example, 200nm, the first and second conductive films constituting a first gateelectrode. Applying a known patterning technique, first conductive films7007, 7008, 7009, 7010 and second conductive films 7012, 7013, 7014,7015 which constitute first gate electrodes are formed.

[0151] When aluminum is used for the second conductive film that is aconstituent of the first gate electrode, pure aluminum as well as analuminum alloy added with a 0.1 to 5 atm % of element selected fromtitanium, silicon and scandium may be used. When copper is used instead,though not shown, it is preferable to form a silicon nitride film on thesurface of the gate insulating film 7006.

[0152] The structure in FIGS. 16A to 16E includes a holding capacitanceportion arranged on the drain side of the n-channel TFT that constitutesthe pixel matrix circuit. At this time, wiring electrodes 7011, 7016 ofthe holding capacitance portion are formed from the same material thatis used to form the first gate electrode.

[0153] After the structure shown in FIG. 16A is formed in this way,doping step with n-type dopant is performed for the first time. As animpurity element for imparting n-type to a crystalline semiconductormaterial, phosphorous (P), arsenic (As), antimony (Sb), etc. are known.Here, phosphorous is used and ion doping is carried out employingphosphine (PH₃). In this step, the acceleration voltage is set to arather high value of 80 keV with the intention of doping through thegate insulating film 7006 the semiconductor layer lying below there withphosphorous. The doped region thus formed are to form first dopedregions 7034, 7042, 7046 of the n-channel TFT which are shown later andserves as an LDD region. Accordingly, phosphorous concentration in thisregion is preferably within a range between 1×10¹⁶ atms/cm³ and 1×10¹⁹atms/cm³, and is set to 1×10¹⁸ atms/cm³ here.

[0154] The impurity element added in the semiconductor active layerneeds to be activated by laser annealing or heat treatment. Althoughthis step may be performed after a doping step for forming source anddrain regions, to activate the element by laser annealing at this stageis very effective.

[0155] The first conductive films 7007, 7008, 7009, 7010 and secondconductive films 7012, 7013, 7014, 7015 which constitute the first gateelectrodes function as masks against phosphorous doping in this step. Asa result, regions of the semiconductor layer beneath the first gateelectrodes, the layer itself lying below the gate insulating film, aredoped with absolutely or almost no phosphorous. Thus, as shown in FIG.16B, lightly doped regions 7017, 7018, 7019, 7020, 7021, 7022, 7023which are doped with phosphorous are formed.

[0156] Next, while using a photoresist film as a mask and coveringregions for forming the n-channel TFTs with resist masks 7024, 7025,doping step to impart p-type is performed only on regions for formingthe p-channel TFT. As an impurity element for imparting p-type, boron(B), aluminum (Al) and gallium (Ga) are known. Here, boron is chosen asthe impurity element and is added by ion doping using dibolane (B₂H₆).The acceleration voltage here is also 80 keV, and the regions are dopedwith boron in a concentration of 2×10²⁰ atms/cm³. Thus, as shown in FIG.16C, regions 7026, 7027 doped with a high concentration of boron areformed. The regions will become source and drain regions of thep-channel TFT.

[0157] After removing the resist masks 7024, 7025, a step of formingsecond gate electrodes is performed. Here, tantalum (Ta) is used for amaterial of the second gate electrodes and a Ta film is formed to have athickness of 100 to 1000 nm, for example, 200 nm. The film is patternedby a known technique to form second gate electrodes 7028, 7029, 7030,7031. The patterning at this time is made in such a way that each secondgate electrode has a length of 5 μm. As a result, each second gateelectrode has on each side of the first gate electrode a region that isin contact with the gate insulating film and that has a length of 1.5μm.

[0158] The holding capacitance portion arranged on the drain side of then-channel TFT that constitutes the pixel matrix circuit has an electrode7032. The electrode 7032 and the second gate electrodes are formedsimultaneously.

[0159] Then, using as masks the second gate electrodes 7028, 7029, 7030,7031, a doping step with an impurity element for imparting n-type isperformed for the second time. As in the first time, ion doping with theuse of phosphine (PH₃) is employed. In this step also, a rather highacceleration voltage of 80 keV is set in order to dope through the gateinsulating film 7006 the semiconductor layer lying below there withphosphorous. The regions doped with phosphorous here function in then-channel TFTs as source regions 7035, 7043 and drain regions 7036,7047.The phosphorous concentration in the regions is therefore preferably setto 1×10¹⁹ to 1×10²¹ atms/cm³, here, 1×10²⁰ atms/cm³.

[0160] Though not illustrated here, a part of the gate insulating filmwhich covers the source regions 7035, 7043 and the drain regions 7036,7047 may be removed so that the semiconductor layer areas correspondingto those regions are exposed and directly doped with phosphorous. Ifthis step is added, the acceleration voltage in the ion doping can bereduced to 10 keV, and phosphorous doping can be efficiently carriedout.

[0161] A source region 7039 and drain region 7040 of the p-channel TFTare doped with the same concentration of phosphorous. However, theregions are doped at the preceding step with boron in a concentrationtwice the phosphorous concentration concerned. Therefore, theconductivity thereof is not inverted, causing no problem in theoperation of the p-channel TFT.

[0162] The impurity elements added in respective concentrations toimpart n-type or p-type are not active by themselves and do not workeffectively, requiring activation step. This step may employ thermalannealing with the use of an electric heating furnace, laser annealingwith the use of the above-mentioned excimer laser, or rapid thermalannealing (RTA) with the use of a halogen lamp.

[0163] In thermal annealing, activation is made by a heat treatment innitrogen atmosphere at 550° C. for 2 hours. The second conductive filmconstituting the first gate electrodes uses aluminum in this embodiment.The aluminum atoms are prevented from diffusing through other regions bya blocking layer of tantalum that forms the first conductive film andthe second gate electrodes both of which cover the aluminum. In laserannealing, activation is made by lineally converging and irradiating KrFexcimer laser light of pulse oscillation type. If thermal annealing iscarried out following laser annealing, even better result is obtained.This step also has an effect of annealing regions with damagedcrystallinity from ion doping, improving the crystallinity of theregions.

[0164] Formed up through the above step are the gate electrodesconsisting of the first gate electrodes and the second gate electrodesthat cover the first gate electrodes, and the source region and thedrain region on each side of the respective second gate electrodes inthe n-channel TFT. Also formed in a self-alignment manner is thestructure in which the first doped region arranged in the semiconductorlayer overlaps through the gate insulating film and the region of thesecond gate electrode which is in contact with the gate insulating film.On the other hand, in the p-channel TFT, a part of the source region anda part of the drain region overlap with the second gate electrode, whichbrings about no problem in practical use.

[0165] Upon obtaining the state of FIG. 16D, a first interlayerinsulating film 7049 is formed to have a thickness of 1000 nm. As thefirst interlayer insulating film 7049, a silicon oxide film, a siliconnitride film, a silicon oxide nitride film, an organic resin film and alaminated film of those may be used. This embodiment employs, though notshown, a two-layer structure in which a silicon nitride film with athickness of 50 nm is first formed and a silicon oxide film with athickness of 950 nm is further formed.

[0166] The first interlayer insulating film 7049 is thereafter patternedto form contact holes in the source regions and drain regions of therespective TFTs. Then, source electrodes 7050, 7052, 7053 and drainelectrodes 7051, 7054 are formed. These electrodes in this embodiment,though not shown, are formed by patterning a three-layer structure filmwith a 100 nm titanium film, a 300 nm aluminum film including titaniumand a 150 nm titanium film which are sequentially formed by sputtering.

[0167] As shown in FIG. 16E, a CMOS circuit and an active matrix circuitare thus formed on the substrate 7001. The holding capacitance portionis simultaneously formed on the drain side of the n-channel TFT in theactive matrix circuit. An active matrix substrate reaches completion asabove.

[0168] Subsequently, a description will be made with reference to FIGS.17A and 17B on a process of manufacturing an LCD panel, based on theCMOS circuit and the active matrix circuit which are formed on the samesubstrate through the above steps. First, on the substrate in the stateof FIG. 16E, a passivation film 7055 is formed to cover the sourceelectrodes 7050, 7052, 7053, the drain electrodes 7051, 7054 and thefirst interlayer insulating film 7049. The passivation film 7055 is madeof a silicon nitride film having a thickness of 50 nm. A secondinterlayer insulating film 7056 made of an organic resin film is furtherformed to have a thickness of about 1000 nm. Usable organic resin filmincludes a polyimide film, an acryl film and a polyimideamide film.Enumerated as advantages in using the organic resin film are: simplefilm formation method; a reduced parasitic capacitance owing to lowrelative permittivity; and excellency in flatness. Other organic resinfilms than the ones mentioned above may also be used. Here, polyimide ofthe type to be thermally polymerized after applied to the substrate isused and burning at a temperature of 300° C. follows to finish the film.

[0169] A light shielding layer 7057 is next formed on a part of a pixelregion of the second interlayer insulating film 7056. The lightshielding layer 7057 may be made of a metal film or an organic resinfilm with pigment contained therein. Here, a titanium film is formed bysputtering.

[0170] After forming the light shielding layer 7057, a third interlayerinsulating film 7058 is formed. This third interlayer insulating film7058 is formed, as is the second interlayer insulating film 7056, usingan organic resin film. A contact hole reaching the drain electrode 7054is formed through the second interlayer insulating film 7056 and thethird interlayer insulating film 7058 to form a pixel electrode 7059.The pixel electrode 7059 uses a transparent conductive film if atransmission type liquid crystal display device is aimed, and a metalfilm is used if a reflection type liquid crystal display device is to bemade. Here, to fabricate a transparent type liquid crystal displaydevice, an indium tin oxide (ITO) film with a thickness of 100 nm isformed by sputtering, forming the pixel electrode 7059.

[0171] When the state of FIG. 17A is obtained, an orientated film 7060is formed. Normally, orientated films for liquid crystal displayelements often use polyimide resins. An opposite side substrate 7071 hasan opposite electrode 7072 and an orientated film 7073 which are formedthereon. After formation, the orientated film is subjected to a rubbingtreatment so that liquid crystal molecules are oriented in parallel witha certain pre-tilt angle.

[0172] Through the steps above, the substrate on which the active matrixcircuit and the CMOS circuit are formed and the opposite substrate arebonded to each other by a known cell assembling process with a sealantand a spacer (both of which are not shown) interposed therebetween.Thereafter, a liquid crystal material 7074 is injected between thesubstrates and an end sealing material (not shown) completely seals thesubstrates. Thus, the LCD panel shown in FIG. 17B is finished.

EMBODIMENT 8

[0173] For the above liquid crystal display devices of the presentinvention, various kinds of liquid crystal may be used other thannematic liquid crystal. For example, usable liquid crystal includes onesdisclosed in: 1998, SID, “Characteristics and Driving Scheme ofPolymer-Stabilized Monostable FLCD Exhibiting Fast Response Time andHigh Contrast Ratio with Gray-Scale Capability” by H. Furue et al.;1997, SID DIGEST, 841, “A Full-Color Thresholdless Antiferroelectric LCDExhibiting Wide Viewing Angle with Fast Response Time” by T. Yoshida etal.; 1996, J. Mater. Chem. 6(4), 671-673, “ThresholdlessAntiferroelectricity in Liquid Crystals and its Application to Displays”by S. Inui et al.; and U.S. Pat. No. 5,594,569.

[0174]FIG. 25 shows electro-optical characteristic of a monostable FLC(Ferroelectric Liquid Crystal). The FLC is prepared such that transitionbetween cholesteric phase and chiral smectic phase is caused whileapplying DC voltage on FLC that exhibits transition system betweenisotropic phase, cholesteric phase and chiral smectic phase, and then,corn edges are aligned substantially in a rubbing direction. The displaymode by ferroelectric liquid crystal as shown in FIG. 25 is called“Half-letter V switching mode”. In the graph shown in FIG. 25, the axisof the ordinate indicates transmittance (arbitrary unit) and the axis ofabscissa indicates applied voltage. Detailed descriptions on the“Half-letter V switching mode” is found in Terada et al. “Half-letter VSwitching Mode FLCD”, Extended Abstracts for The 46th Meeting of TheJapan Society of Applied Physics and Related Societies, p. 1316, [March1999], and Yoshihara et al. “Time Division Full-Color LCD usingFerroelectric Liquid Crystal”, Liquid Crystal (Ekisho), vol. 3 (no. 3),p. 190.

[0175] As shown in FIG. 25, it can be understood that using suchferroelectric mixed liquid crystal makes possible the low-voltagedriving and gradation display. The liquid crystal display devices of thepresent invention may use also ferroelectric liquid crystal that showssuch electro-optical characteristic.

[0176] Liquid crystal that exhibits antiferroelectric phase in a certaintemperature range is called antiferroelectric liquid crystal (AFLC).Among mixed liquid crystal having antiferroelectric liquid crystal,there is one called thresholdless-antiferroelectric mixed liquidcrystal, which exhibits electro-optical response characteristic in thatthe transmittance varies continuously with respect to the electricfield. Some of the thresholdless-antiferroelectric mixed liquid crystalshow electro-optical response characteristic of so-called letter Vshape, and there has been found among them ones the driving voltage ofwhich is about ±2.5 V (cell thickness of about 1 μm to 2 μm).

[0177] In general, thresholdless-antiferroelectric mixed liquid crystalis large in spontaneous polarization and dielectric permittivity ofliquid crystal itself is high. For that reason, a relatively largeholding capacitance is required for a pixel when using for a liquidcrystal display device the thresholdless-antiferroelectric mixed liquidcrystal. Thus, preferably used is thresholdless-antiferroelectric mixedliquid crystal that is small in spontaneous polarization.

[0178] To use such thresholdless-antiferroelectric mixed liquid crystalfor the liquid crystal display devices of the present invention realizesthe low-voltage driving, thereby realizing lowered power consumption.

EMBODIMENT 9

[0179] This embodiment demonstrates a process for producing an EL(electroluminescence) display device as a display of the goggle typedisplay system of the present invention.

[0180]FIG. 19A is a top view showing an EL display device, which wasproduced according to Embodiment 9 of the present application. In FIG.19A, there are shown a substrate 4010, a pixel portion 4011, a sourceside driving circuit portion 4012, and a gate side driving circuitportion 4013, each driving circuit connecting to wirings 4014-4016 whichreach FPC 4017 leading to external equipment.

[0181]FIG. 19B is a sectional view showing the structure of the ELdisplay device in this embodiment. The pixel portion, preferablytogether with the driving circuit portion, is enclosed by a coveringmaterial 6000, a sealing material (or housing material) 7000, and anend-sealing material (or second sealing material) 7001.

[0182] Furthermore, there is shown a substrate 4010, a base film 4021, aTFT 4022 for the driving circuit portion, and a TFT 4023 for the pixelportion. The TFT 4022 shown is a CMOS circuit consisting of an n-channeltype TFT and a p-channel type TFT. The TFT 4023 shown is the one, whichcontrols current to the EL element.

[0183] Upon completion of TFT 4022 (for the driving circuit portion) andTFT 4023 (for the pixel portion), a pixel electrode 4027 is formed onthe interlayer insulating film (planarizing film) 4026 made of a resin.This pixel electrode is a transparent conductive film, which iselectrically connected to the drain of TFT 4023 for the pixel portion.The transparent conductive film may be formed from a compound (calledITO) of indium oxide and tin oxide or a compound of indium oxide andzinc oxide. On the pixel electrode 4027 is formed an insulating film4028, in which is formed an opening above the pixel electrode 4027.

[0184] Subsequently, the EL layer 4029 is formed. It may be ofsingle-layer structure or multi-layer structure by freely combiningknown EL materials such as an injection layer, a hole transport layer, alight emitting layer, an electron transport layer, and an electroninjection layer. Any known technology may be available for suchstructure. The EL material is either a low-molecular material or ahigh-molecular material (polymer). The former may be applied by vapordeposition, and the latter may be applied by a simple method such asspin coating, printing, or ink-jet method.

[0185] In this example, the EL layer is formed by vapor depositionthrough a shadow mask. The resulting EL layer permits each pixel to emitlight differing in wavelength (a red emitting layer, a green emittinglayer, and a blue emitting layer). This realizes the color display.Alternative systems available include the combination of colorconversion layer (CCM) and color filter and the combination of whitelight emitting layer and color filter. Needless to say, the EL displaydevice may be monochromatic.

[0186] On the EL layer 4029 is formed a cathode 4030. Prior to thisstep, it is desirable to clear moisture and oxygen as much as possiblefrom the interface between the EL layer 4029 and the cathode 4030. Thisobject may be achieved by forming the EL layer 4029 and the cathode 4030consecutively in a vacuum, or by forming the EL layer 4029 in an inertatmosphere and then forming the cathode 4030 in the same atmospherewithout admitting air into it. In this Example, the desired film wasformed by using a film-forming apparatus of a multi-chamber system(cluster tool system).

[0187] The multi-layer structure composed of a lithium fluoride film andan aluminum film is used in this Embodiment as the cathode 4030. To beconcrete, the EL layer 4029 is coated by vapor deposition with a lithiumfluoride film (1 nm thick) and an aluminum film (300 nm thick)sequentially. Needless to say, the cathode 4030 may be formed from MgAgelectrode which is a known cathode material. Subsequently, the cathode4030 is connected to a wiring 4016 in the region indicated by 4031. Thewiring 4016 to supply a prescribed voltage to the cathode 4030 isconnected to the FPC 4017 through an electrically conductive pastematerial 4032.

[0188] The electrical connection between the cathode 4030 and the wiring4016 in the region 4031 needs contact holes in the interlayer insulatingfilm 4026 and the insulating film 4028. These contact holes may beformed when the interlayer insulating film 4026 undergoes etching toform the contact hole for the pixel electrode or when the insulatingfilm 4028 undergoes etching to form the opening before the EL layer isformed. When the insulating film 4028 undergoes etching, the interlayerinsulating film 4026 may be etched simultaneously. Contact holes of goodshape may be formed if the interlayer insulating film 4026 and theinsulating film 4028 are made of the same material.

[0189] Then, a passivation film 6003, a filling material 6004 and acovering material 6000 are formed so that these layers cover the ELelement.

[0190] Furthermore, the sealing material 7000 is formed inside of thecovering material 6000 and the substrate 4010 such as surrounding the ELelement, and the end-sealing material (second sealing material) 7001 isformed outside of the sealing material 7000.

[0191] The filling material 6004 is formed to cover the EL element andalso functions as an adhesive to adhere to the covering material 6000.As the filling material 6004, PVC (polyvinyl chloride), an epoxy resin,a silicon resin, PVB (polyvinyl butyral), or EVA (ethylenvinyl acetate)can be utilized. It is preferable to form a desiccant in the fillingmaterial 6004, since a moisture absorption can be maintained.

[0192] Also, spacers can be contained in the filling material 6004. Itis preferable to use spherical spacers comprising barium oxide tomaintain the moisture absorption in the spacers.

[0193] In the case of that the spaces are contained in the fillingmaterial, the passivation film 6003 can relieve the pressure of thespacers. Of course, the other film different from the passivation film,such as an organic resin, can be used for relieving the pressure of thespacers.

[0194] As the covering material 6000, a glass plate, an aluminum plate,a stainless plate, a FRP (Fiberglass-Reinforced Plastics) plate, a PVF(polyvinyl fluoride) film, a Mylar film, a polyester film or an acrylfilm can be used. In a case that PVB or EVA is employed as the fillingmaterial 6004, it is preferable to use an aluminum foil with a thicknessof some tens of m sandwiched by a PVF film or a Mylar film.

[0195] It is noted that the covering material 6000 should have a lighttransparency with accordance to a light emitting direction (a lightradiation direction) from the EL element.

[0196] The wiring 4016 is electrically connected to FPC 4017 through thegap between the sealing material 7000 and the end-sealing material 7001,and the substrate 4010. As in the wiring 4016 explained above, otherwirings 4014 and 4015 are also electrically connected to FPC 4017 underthe sealing material 4018.

EMBODIMENT 10

[0197] In this embodiment, another EL display device having a differentstructure from Embodiment 9 is explained, as shown in FIGS. 20A and 20B.The same reference numerals in FIGS. 20A and 20B as in FIGS. 19A and 19Bindicate same constitutive elements, so an explanation is omitted.

[0198]FIG. 20A shows a top view of the EL module in this embodiment andFIG. 20B shows a sectional view of A-A′ of FIG. 20A.

[0199] According to Embodiment 9, the passivation film 6003 is formed tocover a surface of the EL element.

[0200] The filling material 6004 is formed to cover the EL element andalso functions as an adhesive to adhere to the covering material 6000.As the filling material 6004, PVC (polyvinyl chloride), an epoxy resin,a silicon resin, PVB (polyvinyl butyral), or EVA (ethylenvinyl acetate)can be utilized. It is preferable to form a desiccant in the fillingmaterial 6004, since a moisture absorption can be maintained.

[0201] Also, spacers can be contained in the filling material 6004. Itis preferable to use spherical spacers comprising barium oxide tomaintain the moisture absorption in the spacers.

[0202] In the case of that the spaces are contained in the fillingmaterial, the passivation film 6003 can relieve the pressure of thespacers. Of course, the other film different from the passivation film,such as an organic resin, can be used for relieving the pressure of thespacers.

[0203] As the covering material 6000, a glass plate, an aluminum plate,a stainless plate, a FRP (Fiberglass-Reinforced Plastics) plate, a PVF(polyvinyl fluoride) film, a Mylar film, a polyester film or an acrylfilm can be used. In a case that PVB or EVA is employed as the fillingmaterial 6004, it is preferable to use an aluminum foil with a thicknessof some tens of m sandwiched by a PVF film or a Mylar film.

[0204] It is noted that the covering material 6000 should have a lighttransparency with accordance to a light emitting direction (a lightradiation direction) from the EL element.

[0205] Next, the covering material 6000 is adhered using the fillingmaterial 6004. Then, the flame material 6001 is attached to cover sideportions (exposed faces) of the filling material 6004. The flamematerial 6001 is adhered by the sealing material (acts as an adhesive)6002. As the sealing material 6002, a light curable resin is preferable.Also, a thermal curable resin can be employed if a heat resistance ofthe EL layer is admitted. It is preferable for the sealing material 6002not to pass moisture and oxygen. In addition, it is possible to add adesiccant inside the sealing material 6002.

[0206] The wiring 4016 is electrically connected to FPC 4017 through thegap between the sealing material 6002 and the substrate 4010. As in thewiring 4016 explained above, other wirings 4014 and 4015 are alsoelectrically connected to FPC 4017 under the sealing material 6002.

EMBODIMENT 11

[0207] In this embodiment, the structure of the pixel portion in thepanel is illustrated in more detail. FIG. 21 shows the cross section ofthe pixel portion; FIG. 22A shows the top view thereof; and FIG. 22Bshows the circuit pattern for the pixel portion. In FIG. 21, FIG. 22Aand FIG. 22B, the same reference numerals are referred to for the samenumerals, as being common thereto.

[0208] In FIG. 21, the switching TFT 3002 formed on the substrate 3001can have a TFT structure described in Embodiment 7 of the presentinvention or a conventional TFT structure. In this Embodiment 11, it hasa double-gate structure, but its structure and fabrication process donot so much differ from the structures and the fabrication processesillustrated hereinabove, and their description is omitted herein.However, the double-gate structure of the switching TFT 3002 hassubstantially two TFTs as connected in series, and therefore has theadvantage of reducing the off-current to pass therethrough. In thisEmbodiment, the switching TFT 3002 has such a double-gate structure, butis not limitative. It may have a single-gate structure or a triple-gatestructure, or even any other multi-gate structure having more than threegates.

[0209] The current-control TFT 3003 is an NTFT (n-channel TFT). Thedrain wiring 3035 in the switching TFT 3002 is electrically connectedwith the gate electrode 3037 in the current-control TFT, via the wiring3036 therebetween. The wiring indicated by 3038 is a gate wiring forelectrically connecting the gate electrodes 3039 a and 3039 b in theswitching TFT 3002.

[0210] The current-control TFT is a unit for controlling the quantity ofcurrent that passes through the EL device. Therefore, a large quantityof current passes through it, and the unit, current-control TFT has ahigh risk of thermal degradation and degradation with hot carriers. Tothis unit, therefore, the structure of the invention is favorable, inwhich an LDD region is so constructed that the gate electrode overlapswith the drain area in the current-control TFT, via a gate-insulatingfilm therebetween.

[0211] In this embodiment, the current-control TFT 3003 is illustratedto have a single-gate structure, but it may have a multi-gate structurewith a plurality of TFTs connected in series. In addition, a pluralityof TFTs may be connected in parallel so that the channel-forming regionis substantially divided into plural sections. In the structure of thattype, heat radiation can be effected efficiently. The structure isadvantageous for protecting the device with it from thermaldeterioration.

[0212] As in FIG. 22A, the wiring to be the gate electrode 3037 in thecurrent-control TFT 3003 overlaps with the drain wiring 3040 therein inthe region indicated by 3004, via an insulating film therebetween. Inthis state, the region indicated by 3004 forms a capacitor. Thecapacitor 3004 functions to retain the voltage applied to the gate inthe current-control TFT 3003. The drain wiring 3040 is connected withthe current supply line (power line) 3006, from which a constant voltageis all the time applied to the drain wiring 3040.

[0213] On the switching TFT 3602 and the current-control TFT 3003,formed is a first passivation film 3041. On the first passivation film3041, formed is a planarizing film 3042 of an insulating resin. It isextremely important that the difference in level of the layered parts inTFT is removed through leveling with the planarizing film 3042. This isbecause the EL layer to be formed on the previously formed layers in thelater step is extremely thin, and if there exist a difference in levelof the previously formed layers, the EL device will be often troubled bylight emission failure. Accordingly, it is desirable to previously levelas much as possible the previously formed layers before the formation ofthe pixel electrode thereon so that the EL layer could be formed on theleveled surface.

[0214] The reference numeral 3043 indicates a pixel electrode (a cathodein the EL device) of a conductive film with high reflectivity. The pixelelectrode 3043 is electrically connected with the drain in thecurrent-control TFT 3003. It is preferable that the pixel electrode 3043is of a low-resistance conductive film of an aluminum alloy, a copperalloy or a silver alloy, or of a laminate of those films.Needless-to-say, the pixel electrode 3043 may have a laminate structurewith any other conductive films.

[0215] In the recess (this corresponds to the pixel) formed between thebanks 3044 a and 3044 b of an insulating film (preferably of a resin),the light-emitting layer 3045 is formed. In the illustrated structure,only one pixel is shown, but a plurality of light-emitting layers couldbe separately formed in different pixels, corresponding to differentcolors of R (red), G (green) and B (blue). The organic EL material forthe light-emitting layer may be any-conjugated polymer material. Typicalpolymer materials usable herein include polyparaphenylenevinylene (PVV)materials, polyvinylcarbazole (PVK) materials, polyfluorene materials,etc.

[0216] Various types of PVV-type organic EL materials are known, such asthose disclosed in “H. Shenk, H. Becker, O. Gelsen, E. Klunge, W.Kreuder, and H. Spreitzer; Polymers for Light Emitting Diodes, EuroDisplay Proceedings, 1999, pp. 33-37” and in Japanese Patent Laid-OpenNo. 10-92576. Any of such known materials are usable herein.

[0217] Concretely, cyanopolyphenylenevinylenes may be used forred-emitting layers; polyphenylenevinylenes may be for green-emittinglayers; and polyphenylenevinylenes or polyalkylphenylenes may be forblue-emitting layers. The thickness of the film for the light-emittinglayers may fall between 30 and 150 nm (preferably between 40 and 100nm).

[0218] These compounds mentioned above are referred to merely forexamples of organic EL materials employable herein and are notlimitative at all. The light-emitting layer may be combined with acharge transportation layer or a charge injection layer in any desiredmanner to form the intended EL layer (this is for light emission and forcarrier transfer for light emission).

[0219] Specifically, this Embodiment is to demonstrate an example ofusing polymer materials to form light-emitting layers, which, however,is not limitative. Apart from this, low-molecular organic EL materialsmay also be used for light-emitting layers. For charge transportationlayers and charge injection layers, further employable are inorganicmaterials such as silicon carbide, etc. Various organic EL materials andinorganic materials for those layers are known, any of which are usableherein.

[0220] In this Embodiment, a hole injection layer 3046 of PEDOT(polythiophene) or PAni (polyaniline) is formed on the light-emittinglayer 3045 to give a laminate structure for the EL layer. On the holeinjection layer 3046, formed is an anode 3047 of a transparentconductive film. In this Embodiment, the light having been emitted bythe light-emitting layer 3045 radiates therefrom in the direction towardthe top surface (that is, in the upward direction of TFT). Therefore, inthis, the anode must transmit light. For the transparent conductive filmfor the anode, usable are compounds of indium oxide and tin oxide, andcompounds of indium oxide and zinc oxide. However, since the anode isformed after the light-emitting layer and the hole injection layerhaving poor heat resistance have been formed, it is preferable that thetransparent conductive film for the anode is of a material capable ofbeing formed into a film at as low as possible temperatures.

[0221] When the anode 3047 is formed, the EL device 3005 is finished.The EL device 3005 thus fabricated herein indicates a capacitorcomprising the pixel electrode (cathode) 3043, the light-emitting layer3045, the hole injection layer 3046 and the anode 3047. As in FIG. 22A,the region of the pixel electrode 3043 is nearly the same as the area ofthe pixel. Therefore, in this, the entire pixel functions as the ELdevice. Accordingly, the light utility efficiency of the EL devicefabricated herein is high, and the device can display bright images.

[0222] In this Embodiment, a second passivation film 3048 is formed onthe anode 3047. For the second passivation film 3048, preferably used isa silicon nitride film or a silicon oxynitride film. The object offorming the second passivation film 3048 is to insulate the EL devicefrom the outward environment. The film 3048 has the function ofpreventing the organic EL material from being degraded through oxidationand has the function of preventing it from degassing. With the secondpassivation film 3048 of that type, the reliability of the EL displaydevice is improved.

[0223] As described hereinabove, the EL display panel of the inventionfabricated in this Embodiment has a pixel portion for the pixel havingthe constitution as in FIG. 21, and has the switching TFT through whichthe off-current to pass is very small to a satisfactory degree, and thecurrent-control TFT resistant to hot carrier injection. Accordingly, theEL display panel fabricated herein has high reliability and can displaygood images.

EMBODIMENT 12

[0224] This Embodiment is to demonstrate a modification of the ELdisplay panel of Embodiment 11, in which the EL device 3005 in the pixelportion has a reversed structure. For this Embodiment, referred to isFIG. 23. The constitution of the EL display panel of this Embodimentdiffers from that illustrated in FIG. 22A only in the EL device part andthe current-control TFT part. Therefore, the description of the otherparts except those different parts is omitted herein.

[0225] In FIG. 23, the current-control TFT 3103 may be a PTFT (p-channelTFT).

[0226] In this Embodiment, the pixel electrode (anode) 3050 is of atransparent conductive film. Concretely, used is a conductive film of acompound of indium oxide and zinc oxide. Needless-to-say, also usable isa conductive film of a compound of indium oxide and tin oxide.

[0227] After the banks 3051 a and 3051 b of an insulating film have beenformed, a light-emitting layer 3052 of polyvinylcarbazole is formedbetween them in a solution coating method. On the light-emitting layer3052, formed are an electron injection layer 3053 ofacetylacetonatopotassium, and a cathode 3054 of an aluminum alloy. Inthis case, the cathode 3054 serves also as a passivation film. Thus isfabricated the EL device 3101.

[0228] In this Embodiment, the light having been emitted by thelight-emitting layer 3052 radiates in the direction toward the substratewith TFT formed thereon, as in the direction of the arrow illustrated.

EMBODIMENT 13

[0229] This Embodiment is to demonstrate modifications of the pixel withthe circuit pattern of FIG. 22B. The modifications are as in FIG. 24A toFIG. 24C. In this Embodiment illustrated in those FIG. 24A to FIG. 24C,3201 indicates the source wiring for the switching TFT 3202; 3203indicates the gate wiring for the switching TFT 3202; 3204 indicates acurrent-control TFT; 3205 indicates a capacitor; 3206 and 3208 indicatecurrent supply lines; and 3207 indicates an EL device.

[0230] In the embodiment of FIG. 24A, the current supply line 3206 iscommon to the two pixels. Specifically, this embodiment is characterizedin that two pixels are lineal-symmetrically formed with the currentsupply line 3206 being the center between them. Since the number ofcurrent supply lines can be reduced therein, this embodiment isadvantageous in that the pixel pattern can be much finer and thinner. Inthe embodiment of FIG. 24B, the current supply line 3208 is formed inparallel to the gate wiring 3203. Specifically, in this, the currentsupply line 3208 is so constructed that it does not overlap with thegate wiring 3203, but is not limitative. Being different from theillustrated case, the two may overlap with each other via an insulatingfilm therebetween so far as they are of different layers. Since thecurrent supply line 3208 and the gate wiring 3203 may enjoy the commonexclusive area therein, this embodiment is advantageous in that thepixel pattern can be much finer and thinner.

[0231] The structure of the embodiment of FIG. 24C is characterized inthat the current supply line 3208 is formed in parallel to the gatewirings 3203, like in FIG. 24B, and that two pixels arelineal-symmetrically formed with the current supply line 3208 being thecenter between them. In this, it is also effective to provide thecurrent supply line 3208 in such a manner that it overlaps with any oneof the gate wirings 3203. Since the number of current supply lines canbe reduced therein, this embodiment is advantageous in that the pixelpattern can be much finer and thinner.

EMBODIMENT 14

[0232] The embodiment of Embodiment 11 illustrated in FIG. 22A and FIG.22B is provided with the capacitor 3004 which acts to retain the voltageapplied to the gate in the current-control TFT 3003. In the embodiment,however, the capacitor 3004 may be omitted.

[0233] In the embodiment of Embodiment 11, the current-control TFT 3003is an NTFT with the LDD region being so formed that it overlaps with thegate electrode via the gate-insulating film therebetween. In theoverlapped region, formed is a parasitic capacitance generally referredto as a gate capacitance. Embodiment 14 is characterized in that theparasitic capacitance is positively utilized in place of the capacitor3004.

[0234] The parasitic capacitance varies, depending on the area in whichthe gate electrode overlaps with the LDD region, and is thereforedetermined according to the length of the LDD region in the overlappedarea.

[0235] Also in the embodiments of Embodiment 13 illustrated in FIG. 24A,FIG. 24B and FIG. 24C, the capacitor 3205 can be omitted.

[0236] According to a goggle type display device system of the presentinvention, the system can see the condition of user's body based onuser's vital information obtained by various sensors. If anomaly isrecognized, first video signals given from an external device stop beingdisplayed on LCD panels and outside scenery taken by the system isdisplayed instead. The user may be alarmed by this about anomaly of hisor her body and, further, relaxed by looking at the outside scenerypresented. Also, damage to user's eyesight may be prevented.

What is claimed is:
 1. A goggle type display system comprising: twodisplay devices; first video signals being inputted from an externalvideo signal supplying device; two image capture elements for convertingoutside images into second video signals; a sensor for converting vitalinformation of a user into a vital information signal; and a videosignal control circuit for providing the two display devices with videosignals, wherein the video signal control circuit provides the twodisplay devices with the first video signals or the second video signalson the basis of an index being obtained by numerically processing thevital information signal.